Seasonal Highlights

Climate in China

During Autumn 2008 (September~November), mean surface air temperatures were at least 0.5℃ above normal in most of China, with at least 1℃ above normal in most central-western Northwest China, most Inner Mongolia, most Northeast China, eastern North China, most regions south to the Yangtze River. Temperatures were above 0.5℃ below normal in locations of southeastern Tibet.

For the season, Precipitations were observed at least 30~100% more than normal in most Northwest China, central-western and locations in eastern Inner Mongolia, central-northern North China, eastern and parts of southwestern Tibet, western Jiangnan, western South China and Hainan Province, with over 200% above normal in locations. Meanwhile, precipitations were observed 30~80% below normal in locations of northern Xinjiang, most central and western Tibet, parts of eastern Inner Mongolia, southeastern Northeast China, Huanghai, Jianghuai, with no precipitation in locations of southwestern Xinjiang and most central-western Tibet.

Climate in the World

During Autumn 2008, seasonal mean surface air temperatures were warmer than normal in most of the world. Mean surface air temperatures were observed at least 1℃ above normal in most Eurasia at the mid-high latitudes, most northern Africa, most North America, parts of northern and southern South America, most central-northern Australia, with temperatures 2~4℃ above normal in central-western and northeastern Russia, southern West Asia, central-eastern North Africa, parts of northern and eastern North America, locations in eastern South America and locations in northern Australia. Meanwhile, temperatures were at least 0.5℃ below normal in southwestern Europe, western North Africa, southeastern North America, Alaska and locations in northeastern South America.

For the season, precipitations were observed at least 30% more than normal in most southeastern Russia, central Central Asia, southern Mongolia, most Northwest, parts of northern and southeastern China, Indo-China Peninsula, northeastern South Asia, southern West Asia, parts of western and eastern Africa, central and parts of northern North America, locations in northern South America and most Australia, with over 100% above normal in locations. Meanwhile, precipitations were observed 30~80% below normal in locations of central-northern Russia, northern Mongolia, central-eastern West Asia, central South Asia, locations in Central Asia, most central and eastern North Africa, locations in northern and western North America, locations in South America and locations in Australia, with no precipitation in locations.

General Circulation Features

Northern Hemisphere: During Autumn 2008, in the 500hPa geopotential height anomaly field, positive anomalies above 4 dam covered regions from southeastern Europe to northwestern Central Asia, regions from the northeastern Pacific Ocean to western North America, regions from northeastern North America to the northern North Atlantic Ocean, with central values above 8 dam over locations. Meanwhile, negative anomalies below -4 dam covered locations in northwestern North Africa and locations in southern Alaska in United States. Heights were near normal in other regions.

Southern Hemisphere: For the season, zonal circulation prevailed at the mid-high latitudes. In the 500hPa geopotential height anomaly field, positive anomalies above 4 dam covered the vicinity of 60oS and most regions south to it, the central and locations in the southeastern South Pacific Ocean, with central values above 12 dam over locations. Heights were near normal in other regions.